Transcranial direct current stimulation for major depression: an updated systematic review and meta-analysis

Abstract

Transcranial direct cranial stimulation (tDCS) is a promising non-pharmacological intervention for treating major depressive disorder (MDD). However, results from randomized controlled trials (RCTs) and meta-analyses are mixed. Our aim was to assess the efficacy of tDCS as a treatment for MDD. We performed a systematic review in Medline and other databases from the first RCT available until January 2014. The main outcome was the Hedges' g for continuous scores; secondary outcomes were the odds ratio (ORs) to achieve response and remission. We used a random-effects model. Seven RCTs (n = 259) were included, most with small sample sizes that assessed tDCS as either a monotherapy or as an add-on therapy. Active vs. sham tDCS was significantly superior for all outcomes (g = 0.37; 95% CI 0.04-0.7; ORs for response and remission were, respectively, 1.63; 95% CI = 1.26-2.12 and 2.50; 95% CI = 1.26-2.49). Risk of publication bias was low. No predictors of response were identified, possibly owing to low statistical power. In summary, active tDCS was statistically superior to sham tDCS for the acute depression treatment, although its role as a clinical intervention is still unclear owing to the mixed findings and heterogeneity of the reviewed studies. Further RCTs with larger sample sizes and assessing tDCS efficacy beyond the acute depressive episode are warranted.

A neurocognitive model for understanding treatment action in depression

“…tDCS is a form of non-invasive brain stimulation that involves applying an electric current to the head in order to increase or decrease neuronal excitability. A recent meta-analysis found that anodal stimulation (that is, positively charged stimulation that increases neuronal excitability) of the DLPFC over the course of several days was better than sham tDCS at treating depression [69].…”

Transcranial direct current stimulation may modulate extinction memory in posttraumatic stress disorder

“…This work aligns with the rapidly growing body of research that indicates tDCS may have beneficial effects for psychiatric conditions associated with altered prefrontal activity or connectivity, including depression (Drevets, Price, & Furey, 2008), schizophrenia (Meyer‐Lindenberg et al., 2002), and obsessive–compulsive disorder (Chamberlain et al., 2008). For instance, recent studies have demonstrated tDCS to reduce severity of depression (Brunoni et al., 2013, 2016; Shiozawa et al., 2014) as well as promising results to reduce severity of symptoms associated with schizophrenia (Brunelin et al., 2012; Hoy, Arnold, Emonson, Daskalakis, & Fitzgerald, 2014). Yet, data on the potential effectiveness of tDCS for PTSD are limited to a small sample pilot study reporting improvement on cognitive and emotional performance after working memory training combined with tDCS (Saunders et al., 2015).…”

Strategies for replacing non-invasive brain stimulation sessions: recommendations for designing neurostimulation clinical trials

“…These non-invasive brain stimulation techniques (NIBS) have been shown to improve depression's symptoms, pain, as well as motor and cognitive deficits [2][3][4][5]. From a clinical perspective, to achieve persisting behavioral effects, participants should attend multiple neurostimulation visits [6,7].…”